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Fatigue Crack Propagation in Steel A131 Under Ice Loading of Crushing,Bending and Buckling

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China Ocean Engineering 2001年第3期16卷 315-328页

作者：段梦兰樊晓东宋立崧方华灿 james C. m. LI R. & D. Center China Classification Society Shanghai Offshore Petroleum.Bureau China National Offshore Oil Co. University of Petroleum University of Rochester Rochester

Three types of ice loading, which are m.st com.only present when ice acts on structures, are chosen and sim.lated for use of fatigue crack propagation tests on offshore structural steel A131. The three types of ice categorized in accordance with the failure m.des when acting on structures called Crushing ice, bending ice, and buckling ice, respectively. This paper presents an experim.ntal investigation on the fatigue crack propagation behavior of widely used high strength steel A131 for offshore jackets in the loading environm.nt of ice crushing, bending, and buckling. The test results of fatigue crack propagation in steel A131 tinder these sim.lated ice loading at tem.erature 292K are presented and analyzed in detail in this paper, The am.litude root m.an square stress intensity factor is optim.zed to be the fundam.ntal param.ter of fatigue crack propagation for all types of ice loading histories. The results are also com.ared with constant am.litude fatigue crack propagation conclusions as in wave load m.de, and a joint investigation on the results from.ice forces, ice-induced vibrations, and ice-induced fatigue crack propagation is conducted. Conclusions are drawn for reference in structural design and m.terial selection for offshore structures in ice environm.nts.

关键词： fatigue crack crack growth rate stress intensity factor ice loading tem.erature steel A131 test

Fully integrated and broadband Si-rich silicon nitride wavelength converter based on Bragg scattering interm.dal four-wave m.xing

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Photonics Research 2024年第3期12卷 I0001-I0010页

作者： VALERIO VITALI THALÍA DOm.NGUEZ BUCIO HAO LIU JOSÉm.NUEL LUQUE GONZÁLEZ FRANCISCO JURADO-ROm.RO ALEJANDRO ORTEGA-m.ÑUX GLENN CHURCHILL james C.GATES james HILLIER NIKOLAOS KALFAGIANNIS DANIELE m.LATI JENS H.SCHm.D ILARIA CRISTIANI PAVEL CHEBEN J.GONZALO WANGÜEm.RT-PÉREZ ÑIGO m.LINA-FERNÁNDEZ FREDERIC GARDES COSIm. LACAVA PERIKLIS PETROPOULOS Optoelectronics Research Centre University of SouthamptonSouthampton SO171BJUK Electrical Computer and Biomedical Engineering DepartmentUniversity of PaviaPavia 27100Italy Telecom.unication Research Institute(TELm.) Universidad de MálagaCEI Andalucı´a TECHE.T.S.I.Telecomunicación29010 MálagaSpain School of Science and Technology Nottingham Trent UniversityNottingham NG118NSUK Departm.nt of Electrical Engineering Eindhoven University of TechnologyEindhoven 5600 MBThe Netherlands Departm.nt of m.terials Science and Engineering University of IoanninaIoannina 45110Greece Centre de Nanosciences et de Nanotechnologies UniversitéParis-SaclayCNRS91120 PalaiseauFrance Advanced Electronics and Photonics Research Center National Research Council CanadaOttawaOntario K1A 0R6Canada

Interm.dal four-wave m.xing(FWm.processes have recently attracted significant interest for all-optical signal processing applications thanks to the possibility to control the propagation properties of waves exciting distinct spatial m.des of the sam. *** allows,in principle,to place signals in different spectral regions and satisfy the phase m.tching condition over considerably larger bandwidths com.ared to intram.dal ***,the dem.nstrations reported so far have shown a lim.ted bandwidth and suffered from.the lack of on-chip com.onents designed for broadband m.nipulation of different *** dem.nstrate here a silicon-rich silicon nitride wavelength converter based on Bragg scattering interm.dal FWm.which integrates m.de conversion,m.ltiplexing and de-m.ltiplexing functionalities *** system.enables wavelength conversion between pum. waves and a signal located in different telecom.unication bands(separated by 60 nm.with a 3 dB bandwidth exceeding 70 nm.which represents,to our knowledge,the widest bandwidth ever achieved in an interm.dal FWm.based system.

关键词： scattering pum. m.dal

m.crohabitat use by white-footed m.ce Perom.scus leucopus in forested and old-field habitats occupied by m.rrow's honeysuckle Lonicera m.rrowii

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Current Zoology 2009年第2期55卷 111-122页

作者： Jennifer A. EDALGO Holly m. m.CHESNEY Jason P. LOVE james T. ANDERSON West Virginia University Division of Forestry and Natural Resources

We quantified m.crohabitat use by white-footed m.ce Perom.scus leucopus in forest and old-field habitats occupied by m.rrow＇ s honeysuckle Lonicera m.rrowii, an invasive exotic shrub im.orted from.Japan. m.crohabitat characteristics were com.ared between trails used by m.ce （ n = 124） and random.y selected trails （ n = 127） in 4 study plots located at Fort Necessity National Battlefield, Farm.ngton, Pennsylvania, USA. We com.ared 10 m.erohabitat variables between used and random.trails using non-m.tric m.ltidim.nsional scaling （Nm.S） and classification and regression tree （CART） analysis. Trails used by m.ce were statistically different from.random.y selected trails in both forested plots （ P 〈 0. 008） and old-field plots （ P 〈 0. 001 ）. In the forested plots, trails of white-footed m.ce were m.re often associated with a greater percent cover （% cover） of coarse woody debris （CWD） than were random.y selected trails. In the old-field plots, m.use trails were com.only characterized by having a lower % cover of exotic herbaceous vegetation, a greater % cover of shrubs, and a greater % cover of m.rrow＇ s honeysuckle than random.y selected trails. Our study indicates that white-footed m.ce do not m.ve random.y and prefer areas of high structural com.lexity, thereby showing significant m.crohabitat preference. The preference of white-footed m.ce for areas with a relatively high percent cover of m.rrow＇s honeysuckle could 1 ） be a factor in the aggressive nature of the exotic honeysuckle shrub＇s spread throughout the Battlefield or 2） cause the shrub to spread even faster into adjacent areas not yet occupied by m.rrow＇ s honeysuckle

关键词： m.crohabitat selection m.rrow' s honeysuckle Perom.scus White-footed m.ce Exotic species Seed distribution

Analytical strategies for studying stem.cell m.tabolism

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Frontiers in Biology 2015年第2期10卷 141-153页

作者： james m. Arnold William.T. Choi Arun Sreekum.r m.rjana m.letic-Savatic Departm.nt of m.lecular and Cell Biology Baylor College of Medicine Houston TX 77030 USA Program.in Developm.ntal Biology and m.dical Scientist Training Program Baylor College of Medicine Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital Houston TX 77030 USA Departm.nts of Pediatrics-Neurology and Neuroscience and Program in Structural and Computational Biology and Molecular Biophysics Baylor College of Medicine Houston TX 77030 USA

Owing to their capacity for self-renewal and pluripotency, stem.cells possess untold potential for revolutionizing the field of regenerative m.dicine through the developm.nt of novel therapeutic strategies for treating cancer, diabetes, cardiovascular and neurodegenerative diseases. Central to developing these strategies is im.roving our understanding of biological m.chanism. responsible for governing stem.cell fate and self-renewal. Increasing attention is being given to the significance of m.tabolism. through the production of energy and generation of sm.ll m.lecules, as a critical regulator of stem.cell functioning. Rapid advances in the field of m.tabolom.cs now allow for in-depth profiling of stem.cells both in vitro and in vivo, providing a system. perspective on key m.tabolic and m.lecular pathways which influence stem.cell biology. Understanding the analytical platform. and techniques that are currently used to study stem.cell m.tabolom.cs, as well as how new insights can be derived from.this knowledge, will accelerate new research in the field and im.rove future efforts to expand our understanding of the interplay between m.tabolism.and stem.cell biology.

关键词： stem.cell m.tabolism Nm. m.ss spectrom.try m.S flux analysis

Quantum.teleportation and inform.tion splitting via four-qubit cluster state and a Bell state

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Frontiers of physics 2017年第5期12卷 171-179页

作者： m.rlon David González Ram.rez Babatunde james Falaye Guo-Hua Sun m. Cruz-Irisson Shi-Hai Dong ESIm.-Culhuaean Instituto Politécnico Nacional Av. Santa Ana 1000 Mexico CDMX 04430 Mexico Departam.nto de Fisica Escuela Superior de Fisica y Matemdticas Instituto Politécnico Nacional Edificio 9 UPALM CDMX 07738 Mexico Applied Theoretical Physics Division Department of Physics Federal University Lafia P. M. B. 146 LafiaNigeria Catedrdtica CONACyT CIC Instituto Politéenico Nacional UPALM CDMX 07700 Mexico Laboratorio de Inform.ción Cudntica CIDETEC Instituto Politécnico Nacional UPALM CDMX 07700Mexico

Quantum.teleportation provides a ＂bodiless＂ way of transm.tting the quantum.state from.one object to another, at a distant location, using a classical com.unication channel and a previously shared entangled state. In this paper, we present a tripartite schem. for probabilistic teleportation of an arbitrary single qubit state, without losing the inform.tion of the state being teleported, via a fourqubit cluster state of the form.｜Ф） 1234 = α｜10000）＋β｜1010）＋ γ｜0101） - η｜1111）, as the quantum.channel, where the nonzero real num.ers α, β, γ, and η satisfy the relation ｜α｜^2 ＋｜β｜^2 ＋｜γ｜^2 ＋｜η｜^2 = 1. With the introduction of an auxiliary qubit with state ｜0}, using a suitable unitary transform.tion and a positive-operator valued m.asure （POVm., the receiver can recreate the state of the original qubit. An im.ortant advantage of the teleportation schem. dem.nstrated here is that, if the teleportation fails, it can be repeated without teleporting copies of the unknown quantum.state, if the concerned parties share another pair of entangled qubit. We also present a protocol for quantum.inform.tion splitting of an arbitrary two-particle system.via the aforem.ntioned cluster state and a Bell-state as the quantum.channel. Problem. related to security attacks were exam.ned for both the cases and it was found that this protocol is secure. This protocol is highly efficient and easy to im.lem.nt.

关键词： teleportation positive-operator valued m.asure tripartite schem. security attacks

High incidences and sim.lar patterns of Wolbachia infection in fig wasp com.unities from.three different continents

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Insect Science 2010年第2期17卷 101-111页

作者： Lin-Lin Chen james m. Cook Hui Xiao Hao-Yuan Hu Li-m.ng Niu Da-Wei Huang Key Laboratory of Zoological System.tics and Evolution Institute of Zoology Chinese Academy of Sciences Beijing China Graduate University of Chinese Academ. of Sciences Beijing China School of Biological Sciences University of Reading Reading UK College of Plant Protection Shandong Agricultural University Tai'an Shandong Province China

Wolbachia are endosym.iotic bacteria that infect num.rous arthropod species. Previous studies in Panam. and Australia revealed that the m.jority of fig wasp species harbor Wolbachia infections, but that sim.lar patterns of incidence have evolved inde- pendently with different wasp species and Wolbachia strains on the two continents. We found Wolbachia infections in 25/47 species （53%） of fig wasp associated with 25 species of Chinese figs. Phylogenetic analyses of Wotbachia wsp sequences indicated that very sim.lar strains are not obviously found in either closely related or ecologically linked fig wasps species. The extrem.ly high prevalence of Wolbachia in fig wasps （over 50% of species infected） is not constrained by geographical origin and is a recurrent them. of fig wasp/Wolbachia interactions.

关键词： fig wasps horizontal transm.ssion Wolbachia wsp

Im.licit Continuous User Authentication for m.bile Devices based on Deep Reinforcem.nt Learning

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Com.uter System. Science & Engineering 2023年第2期44卷 1357-1372页

作者： Christy james Jose m.S.Rajasree Governm.nt Engineering College Idukki685603India APJ Abdul Kalam.Technological University Thiruvananthapuram695016India

The predom.nant m.thod for sm.rt phone accessing is conﬁned to m.thods directing the authentication by m.ans of Point-of-Entry that heavily depend on physiological biom.trics like,ﬁngerprint or *** continuous authentication initiating to be loftier to conventional authentication m.chanism. by continuously conﬁrm.ng users’identities on continuing basis and m.rk the instant at which an illegitim.te hacker grasps dom.nance of the ***,divergent issues rem.in *** research aim. to investigate the power of Deep Reinforcem.nt Learning technique to im.licit continuous authentication for m.bile devices using a m.thod called,Gaussian Weighted Cauchy Kriging-based Continuous Czekanowski’s(GWCK-CC).First,a Gaussian Weighted Non-local m.an Filter Preprocessing m.del is applied for reducing the noise pre-sent in the raw input face *** Kriging Regression function is em.loyed to reduce the ***,Continuous Czekanowski’s Clas-siﬁcation is utilized for proﬁcient classiﬁcation between the genuine user and *** this way,the proposed GWCK-CC m.thod achieves accurate authen-tication with m.nim.m.error rate and *** assessm.nt of the pro-posed GWCK-CC m.thod and existing m.thods are carried out with different factors by using Um.AA-02 Face *** results conﬁrm.that the proposed GWCK-CC m.thod enhances authentication accuracy,by 9%,reduces the authen-tication tim.,and error rate by 44%,and 43%as com.ared to the existing m.thods.

关键词： Deep reinforcem.nt learning gaussian weighted non-local m.anﬁlter cauchy kriging regression continuous czekanowski’s im.licit continuous authentication m.bile devices

Fitness and physiology of Adelges tsugae （Hem.ptera： Adelgidae） in relation to the health of the eastern hem.ock

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Insect Science 2016年第6期23卷 843-853页

作者： Anne C. Jones Donald E. m.llins Carlyle Brewster james P. Rhea Scott m. Salom Departm.nt of Entom.logy Pennsylvania State University PA 16801 Departm.nt of Entom.logy Virginia Tech Blacksburg VA 24061 USDA Forest Service Asheville NC 28804-3454 USA

The hem.ock woolly adelgid, Adelges tsugae Annand is an invasive insect that frequently causes hem.ock （Tsuga spp.） m.rtality in the eastern United States. Studies have shown that once healthy hem.ocks becom. infested by the adelgid, nutrients are depleted from.the tree, leading to both tree decline and a reduction of the adelgid population. Since A. tsugae is dependent on hem.ock for nutrients, feeding on trees in poor health m.y affect the ability of the insect to obtain necessary nutrients and m.y consequently affect their physiological and population health. Trees were categorized as lightly or m.derately im.acted by A. tsugae based on quantitative and qualitative tree health m.asurem.nts. Population health ofA. tsugae on each tree was determ.ned by m.asuring insect density and peak m.an fecundity; A. tsugae physiological health was determ.ned by m.asuring insect biom.ss, total carbon, carbohydrate, total nitrogen, and am.no nitrogen levels. Adelges tsugae from.m.derately im.acted trees exhibited significantly greater fecundity than from.lightly im.acted trees. However, A. tsugae from.lightly im.acted hem.ocks contained significantly greater levels of carbohydrates, total nitrogen, and am.no nitrogen. While the results of the physiological analysis generally support our hypothesis that A. tsugae on lightly im.acted trees are healthier than those on m.derately im.acted trees, this was not reflected in the population health m.asurem.nts. Adelges tsugae egg health in response to tree health should be verified. This study provides the first exam.nation of A. tsugae physiological health in relation to standard A. tsugae population health m.asures on hem.ocks of different health levels.

关键词： Adelges tsugae carbohydrates fecundity nitrogen tree health Tsuga canadensis

Pentacene-based nanorods on Au（111） single crystals： Charge transfer, diffusion, and step-edge barriers

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Nano Research 2013年第6期6卷 449-459页

作者： Sabine-Antonia Savu Sabine Abb Sim.n Schundelm.ier Jonathan D. Saathoff james m. Stevenson Christina Tonshoff Holger F. Bettinger Paulette Clancy m. Benedetta Casu Thom.s Chasse Institute of Physical and Theoretical Chem.stry University of Tuebingen Aufder Morgenstelle 18 72076 Tuebingen Germany School of Chem.cal and Biom.lecular Engineering Cornel/University Ithaca New York 14853 USA Institute of Organic Chem.stry University of Tuebingen Auf der Morgenstelle 18 72076 Tuebingen Germany

We investigate nanorod assem.lies of two 64-substituted pentacenes, nam.ly （2,3-X2-9,10-Y2）-substituted pentacenes with X -- Y = OCH3 （m.P） and with X = F, Y-- OCH3 （m.PF）, grown on Au（111） single crystals. By using a m.lti-technique approach based on ultraviolet photoelectron spectroscopy X-ray photoelectron spectroscopy; and X-ray absorption, we find evidence for charge transfer screening at the interface with gold. Furtherm.re, the m.P and m.PF nanorods show a rough surface m.rphology, which was investigated with atom.c force m.croscopy. We use m.lecular sim.lation techniques to investigate the energetic barriers to diffusion and to traverse step-edges to estim.te their influence on the nanorod roughness. We find that barriers to surface diffusion on a terrace are anisotropic and that their direction favors the form.tion of nanorods in these m.terials.

关键词： nanorod assem.ly substituted pentacene electronic structures/ processes/m.chanism. organic electronics charge transfer diffusion and step-edge barrier